GST Activity Research Articles

Dynamics of HSPA1A and redox status in the spermatozoa and fluid from different segments of goat epididymis.

The present study was attempted to investigate the dynamics of HSPA1A and redox status in the spermatozoa and fluid of different segments of buck epididymis. Testes were collected from sexually mature and healthy bucks aged between 2 and 3years. The fluid and spermatozoa from different segments (caput, corpus and cauda) were harvested for further processing and analysis. The concentration of HSPA1A in spermatozoa lysate and epididymal fluid and its relative mRNA expression in spermatozoa from different segments of epididymis were studied. The HSPA1A concentration in epididymal fluid was significantly (P < 0.01) higher in the corpus as compared with caput and cauda, whereas, its concentration and relative mRNA expression decreased significantly (P < 0.01) in the spermatozoa from caput to cauda. The activities of SOD, GR, GST, and concentrations of manoldialdehyde and ROS decreased significantly (P < 0.01) in the spermatozoa from caput to cauda. The glutathione concentration and GPx activity decreased significantly (P < 0.01) in the spermatozoa of cauda as compared with the corpus. The SOD activity and ROS concentration were significantly (P < 0.01) higher in corpus, and GR and GST activity were significantly (P < 0.01) higher in caput fluid as compared with corpus and cauda. It may be concluded that HSPA1A concentration and its relative mRNA expression in spermatozoa decreased progressively, and redox status was altered during transit from caput to cauda.

Lipophosphoglycan-3 recombinant protein vaccine controls hepatic parasitism and prevents tissue damage in mice infected by Leishmania infantum chagasi

AimsIn this work, we aimed to evaluate the effects of the Leishmania infantum chagasi infection on the liver of vaccinated mice, considering parameters of tissue damage and the inflammatory response elicited by vaccination. Main methodsWe used recombinant LPG3 protein (rLPG3) as immunogen in BALB/c mice before challenge with promastigote forms of L. infantum chagasi. The animals were separated into five groups: NI: non-infected animals; NV: non-vaccinated; SAP: treated with saponin; rLPG3: immunized with rLPG3; rLPG3 + SAP: immunized with rLPG3 plus SAP. The experiment was conducted in replicate, and the vaccination protocol consisted of three subcutaneous doses of rLPG3 (40 μg + two boosters of 20 μg). The mice were challenged two weeks after the last immunization. Key findingsOur results showed that rLPG3 + SAP immunization decreased the parasite burden in 99 %, conferring immunological protection in the liver of the infected animals. Moreover, the immunization improved the antioxidant defenses, increasing CAT and GST activity, while reducing the levels of oxidative stress markers, such as H2O2 and NO3/NO2, and carbonyl protein in the organ. As a consequence, rLPG3 + SAP immunization preserved tissue integrity and reduced the granuloma formation, inflammatory infiltrate and serum levels of AST, ALT, and ALP. SignificanceTaken together, these results showed that rLPG3 vaccine confers liver protection against L. infantum chagasi in mice, while maintaining the liver tissue protected against the harmful inflammatory effects caused by the vaccine followed by the infection.

Roundup-induced biochemical and histopathological changes in the liver and kidney of rats: the ameliorative effects of Linum usitatissimum oil.

The present study was undertaken to evaluate the protective effects of Linum usitatissimum oil (LuO) against sub-chronic Roundup (RDP)-induced toxicity and oxidative stress in rats. Rats were divided into four groups: control group (no treatment), RDP group (Roundup at 269.9 mg/kg b.w.), LuO group (0.5 g/kg b.w. of LuO) and RDP+LuO group (RDP and LuO simultaneously). LuO decreased the ferric reducing antioxidant power (FRAP) (IC50=10.36 μg/ml) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) (IC50=22.85 mg/ml) in the tested tissues. The 30-day exposure of rats to RDP caused an increase in serum hepatic and renal markers: AST, ALT, ALP, LDH, γGT, bilirubin, urea, and creatinine. In addition, SOD, CAT and GST activities decreased by 43%, 61%, and 61%, respectively, while GPx activity, MDA and PCOs levels increased by 80%, 46%, 25%, respectively. LuO treatment alleviated hepatotoxicity in RDP-treated rats, showing improved levels of oxidative stress biomarkers and plasma biochemical parameters. The histological examination of the liver and kidney confirmed the changes in Roundup-treated rats and demonstrated the protective role of LuO.

Corrigendum

Corrigendum

Spermatogenic Apoptosis and the Involvement of the Nrf2 Pathway in Male Mice Following Exposure to Nano Titanium Dioxide.

Titanium dioxide nanoparticles (TiO₂ NPs) are largely manufactured and extensively applied for the treatment of environmental pollution. Studies have proved that exposure to TiO₂ NPs leads to toxicity of the reproductive system. However, very few studies have highlighted the involvement of nuclear factor erythroid-2 related factor 2 (Nrf2) under TiO₂ NPinduced spermatogenic apoptosis. Our findings suggested that TiO₂ NPs could cross the blood-testis barrier and were aggregated or deposed in spermatogenic cells, which resulted in spermatogenic apoptosis. Furthermore, exposure to TiO₂ NPs caused an overproduction of reactive oxygen species and the peroxidation of lipids, proteins, and DNA. Such exposure also caused significant decreases in the activities of SOD, GSH-PX, GST, and GSH content in the testis. Importantly, exposure to TiO₂ NPs resulted in an up-regulation of Keap1 expression and a down-regulation of Nrf2 and its target gene products, NQO1, HO-1, GCLC, PKC, and PI3K. The present study implies that TiO₂ NPs could lead to spermatogenic apoptosis, and Nrf2 is the initial factor that responded to such reproductive toxicity by regulating the expression of antioxidative proteins.

Ebselen reversed peripheral oxidative stress induced by a mouse model of sporadic Alzheimer's disease.

Intracerebroventricular streptozotocin injection (icv STZ) is a well established sporadic Alzheimer's disease (AD) model in rodents. AD is characterized by neuronal degeneration accompanied by central oxidative stress. Studies also indicate peripheral oxidative damage in AD, but if the icv STZ model of sporadic AD mimics this feature is an open question. This study aimed to investigate if icv STZ administration induces peripheral oxidative stress and the antioxidant action of Ebselen, compared to the reference drug (donepezil), in this sporadic AD model. Male adult Swiss mice received icv STZ (days 1 and 3). Mice received Ebselen (10mg/kg, i.p) or Donepezil (5mg/kg, i.p) for 14days. Mice were killed and the kidney and liver were excised to determine parameters of oxidative stress and toxicity markers. The mice icv STZ-injected showed peripheral oxidative stress. Ebselen reversed renal lipid peroxidation in the icv STZ administered mice by modulating NPSH levels, SOD and CAT activities, whereas Donepezil, modulated only NPSH levels. Ebselen and Donepezil counteracted hepatic lipid peroxidation in STZ-injected mice by modulating NPSH levels and CAT activity. The δ-ALA-D activity was inhibited in the kidney, but not in the liver, whereas the icv STZ-injected mice had an increase in the GST activity in both tissues. Ebselen reversed the increase in the hepatic GST activity of the STZ-injected mice. Donepezil increased renal GST activity in the control mice. In conclusion, this study demonstrates that the icv STZ administration induced peripheral oxidative stress. Ebselen, similar to Donepezil, was effective against peripheral oxidative stress in a mouse model of sporadic AD.

The Oxidative Stress Markers in the Erythrocytes and Heart Muscle of Obese Rats: Relate to a High-Fat Diet but Not to DJOS Bariatric Surgery.

Obesity and high-fat diet (HF) are prevalent causes of oxidative stress (OS). Duodenal-jejunal omega switch (DJOS) is a bariatric procedure used for body mass reduction, extensively tested in animal models. We studied the long-term impact of bariatric surgery and an HF diet on the oxidative stress markers in erythrocytes and heart muscles of rats. We analyzed superoxide dismutase (SOD), catalase (CAT), glutathione transferase (GST), glutathione reductase (GR), glutathione peroxidase (GPx) activity and malondialdehyde (MDA) concentration in DJOS or SHAM (control) operated rats fed with different dietary protocols (control diet (CD) and high-fat diet (HF)), before and after the surgery (CD/CD, HF/HF, CD/HF, and HF/CD). We observed higher erythrocytes CAT, GST and GPx activity in DJOS-operated (vs. SHAM) rats fed with an HF/HF diet. For DJOS-operated rats, erythrocytes CAT and GPx activity and MDA concentration were significantly lower in CD/CD group. We observed increased heart muscle GR activity in SHAM-operated rats (vs. DJOS bariatric surgery) fed with an HF/HF diet. Change from HF to CD diet increased heart muscle GPx activity after DJOS bariatric surgery. Heart muscle SOD activity was lower in HF/HF and CD/CD groups after DJOS bariatric surgery (vs. SHAM). DJOS surgery significantly reduced heart muscle MDA concentration in HF/HF and HF/CD groups (vs. SHAM). We conclude that the selected dietary patterns had a stronger impact on oxidative stress markers in erythrocytes and heart muscle than DJOS bariatric surgery.

Effect of air pre-exposure on Tetrabromobisphenol A resistance in the clam Ruditapes philippinarum

The present study was conducted to evaluate how air pre-exposure influences the responses in gills and digestive gland of Ruditapes philippinarum on subsequent Tetrabromobisphenol A (TBBPA) exposure. Firstly, clams were maintained in seawater or pre-exposed to air for 24 h, and then exposed to 0 or 100 μg/L TBBPA. Clam tissues were sampled after 1 day (T1) and 7 days (T7) of exposure to TBBPA. The results showed that in comparison with TBBPA exposure alone, air pre-exposure following TBBPA exposure reduced TBBPA accumulation in both tissues, up-regulated mRNA levels of CAT, Hsp70 and pi-GST in gills, and induced GST activity and P-glycoprotein (Pgp) mRNA level in digestive gland of clams at T1, whereas increased lipid peroxidation at T7. Overall, the findings indicate that 24-h exposure to air can activate a priming mechanism withstanding the subsequent TBBPA exposure, which is transient and may change after prolonged subsequent exposure.

Responses of the Nrf2/Keap1 signaling pathway in Mugilogobius abei (M. abei) exposed to environmentally relevant concentration aspirin

Aspirin (ASA) is a widely used non-steroidal anti-inflammatory drug. Its high detection frequency in various waterborne and environmental residues has drawn wide attention. Limited information were provided for the effects of aspirin exposure on oxidative stress signaling pathway in fish, which is closely related to pathological and immunological process of fish. In this study, a small fish - Mugilogobius abei (M. abei) distributing widely in aquatic ecosystems in southern China, was employed as testing organism and the key genes of the detoxification metabolism were cloned for the first time. The responses of Nrf2/Keap1 signaling pathway were investigated under the environmentally relevant concentration aspirin exposure (0.5μgL-1, 5μgL-1, and 50μgL-1) for 24h, 72h, and 168h then. The transcriptional expression of the key genes (Nrf2, Keap1, GCLC, GPx, GST, SOD, CAT, Trx2, and TrxR) as well as the changes of the related enzymatic activities (GPx, GST, SOD, and CAT) and GSH and MDA content were also determined. Results showed that Nrf2 and Keap1 gene expression displayed a negative correlation to some extent under ASA exposure, the transcriptional expressions of the downstream related genes (GCLC, GST, SOD, CAT, Trx2, and TrxR) in Nrf2/Keap1 signaling pathway showed inhibition at 24h but induction at 72h and 168h. At the protein level, ASA exposure can improve the antioxidant capacity by increasing GSH synthesis and enzymatic activity of GPx, GST, SOD, and CAT to reduce the degree of lipid peroxidation. We proposed that ASA exposure may interfere with the redox balance in M. abei at an early stage but sub-chronic ASA exposure can activate the Nrf2 signaling pathway to improve the antioxidant capacity of M. abei.

Abamectin resistance and resistance mechanisms in Tetranychus urticae populations from cut flowers greenhouses in Turkey

ABSTRACTTetranychus urticae Koch is a common pest of many crops in Turkey and the world. In this study, abamectin LC values, resistance rates, detoxification enzyme activities and the presence of G314D point mutation in the target site were investigated in T. urticae collected from cut flower production greenhouses in Antalya. The LC values of the susceptible and field populations were determined by spray tower-leaf disc method. The resistance rates of field populations ranged from 1.60 to 850.12-fold compared to the susceptible population. Activities of three detoxification enzymes were determined by a microplate reader. The activity of esterase and GST ranged from 4.04 to 8.21 and from 4.40 to 11.69 mOD min−1 mg−1 proteins, respectively, in different populations. On the other hand, the P450 enzyme activity of the field populations was 0.52-1.80 RFU 30 min-1 mg-1 protein. Screening the populations for the presence of G314D point mutation in glutamate-gated chloride channels (GluCls) by real-time PCR using the mutation-specific TaqMan probe revealed no mutations in any populations tested. The results showed that the resistance in the populations tested in this study is likely associated with activity of detoxifying enzymes rather than target site mutations in the GluCls channels.

Chemopreventive Effect of the Germinated Oat and its Phenolic-AVA Extract in Azoxymethane/Dextran Sulfate Sodium (AOM/DSS) Model of Colon Carcinogenesis in Mice.

The consumption of fruits, vegetables, nuts, legumes, and whole grains has been associated with a lower risk of colorectal cancer (CRC) due to the content of natural compounds with antioxidant and anticancer activities. The oat (Avena sativa L.) is a unique source of avenanthramides (AVAs), among other compounds, with chemopreventive effects. In addition, oat germination has shown enhanced nutraceutical and phytochemical properties. Therefore, our objective was to evaluate the chemopreventive effect of the sprouted oat (SO) and its phenolic-AVA extract (AVA) in azoxymethane (AOM)/dextran sulfate sodium (DSS)-induced CRC mouse model. Turquesa oat seeds were germinated (five days at 25 °C and 60% relative humidity) and, after 16 weeks of administration, animals in the SO- and AVA-treated groups had a significantly lower inflammation grade and tumor (38–50%) and adenocarcinoma (38–63%) incidence compared to those of the AOM+DSS group (80%). Although both treatments normalized colonic GST and NQO1 activities as well as erythrocyte GSH levels, and significantly reduced cecal and colonic β-GA, thus indicating an improvement in the intestinal parameters, the inflammatory states, and the redox states of the animals, SO exerted a superior chemopreventive effect, probably due to the synergistic effects of multiple compounds. Our results indicate that oats retain their biological properties even after the germination process.

Yeast glutaredoxin, GRX4, functions as a glutathione S-transferase required for red ade pigment formation in Saccharomyces cerevisiae

The adenine biosynthetic mutants ade1 and ade2 of Saccharomyces cerevisiae accumulate a characteristic red pigment in their vacuoles under adenine limiting conditions. This red pigmentation phenotype, widely used in a variety of genetic screens and assays, is the end product of a glutathione-mediated detoxification pathway, where the glutathione conjugates are transported into the vacuole. The glutathione conjugation step, however, has still remained unsolved. We show here, following a detailed analysis of all the members of the thioredoxinfold superfamily, the involvement of the monothiol glutaredoxin GRX4 as essential for pigmentation. GRX4 plays multiple roles in the cell, and we show that the role in ade pigmentation does not derive from its regulatory role of the iron transcription factor, Aft1p, but a newly identified GST activity of the protein that we could demonstrate using purified Grx4p. Further, we demonstrate that the GRX domain of GRX4 and its active site cysteine C171 is critical for this activity. The findings thus solve a decades old enigma on a critical step in the formation of this red pigmentation.

Etoxazole stereoselective determination, bioaccumulation, and resulting oxidative stress in Danio rerio (zebrafish).

An environmentally-friendly and fast analytical method for the stereoselective determination of etoxazole was developed and then applied to estimate stereoselective bioaccumulation and elimination in zebrafish using SFC-MS/MS. Optimal enantioseparation conditions were determined using a Chiralpak IG-3 column and CO2/MeOH mobile phase (80/20, v/v), at 3.0mL/min within 1min, 30°Me and 18MPa. A modified QuEChERS method was developed for zebrafish sample pretreatment, and mean recoveries were 88.43-110.12% with relative standard deviations ranging from 0.32 to 5.34%. The enantioselectives of etoxazole enantiomers in zebrafish during uptake and depuration phases were evaluated. Significant enantioselective bioaccumulation was observed, with preferential accumulation of (-)-R-etoxazole compared to its antipode, during uptake at both low and high exposure concentrations. The toxic effects of etoxazole on zebrafish were further explored, and activities of antioxidant enzymes were determined in liver of zebrafish. Significant changes were observed in the SOD and GST activities and in the MDA levels, which indicated the occurrence of oxidative stress in liver of zebrafish. The toxic effects exhibited time- and dose-dependent properties. These results can facilitate the accurate risk evaluation of etoxazole and provide basic knowledge for further study of biotoxicity mechanisms.

Protective effect of Echinochrome against intrahepatic cholestasis induced by alpha-naphthylisothiocyanate in rats.

The present study was designed to evaluate the protective effects of echinochrome (Ech) on intrahepatic cholestasis in rats induced by a single (i.p.) injection of alpha-naphthylisothiocyanate (ANIT) (75 mg/kg body weight). The rats were pre-treated orally for 48hr (one dose / 24hr) with Ech (1, 5 and 10 mg/kg body weight) or ursodeoxycholic acid (UDCA) 80 mg/kg body weight drug then, injected with ANIT. ANIT markedly increased serum activities of alanine amino transaminase (ALT), aspartate amino transaminase (AST) and alkaline phosphatase (ALP), which was accompanied by a massive inflammation of epithelial cells on bile duct at 24h after ANIT injection. ANIT also increased the levels of total protein (TP), total bilirubin (TB), direct bilirubin (DB), indirect bilirubin (IB), however decrease albumin content (ALB). In addition ANIT increased hepatic MDA and NO level and decreased GSH level and GST activity. The Ech exerted hepatoprotective and anticholestatic effects as assessed by a significant decrease in the activities of serum AST, ALT and ALP, and the levels of TP, TB, DB and IB as well as liver MDA level and NO level. In conclusion, Ech was found to possess hepatoprotective effect against intrahepatic cholestasis induced by hepatotoxin such as ANIT.

English

The use of antimicrobial agents and antibiotics as remedial measures against fish diseases has been questioned. The huge amounts of antibiotics used in animal husbandry has exerted a very strong selection pressure on the resistance among bacteria, which have adapted to this situation, mainly by a horizontal and philandering flow of resistance genes. Prebiotics, probiotics and symbiotics have been proposed as strategic means to enhance feed utilization, growth and immunity in fish production. In the present trial, a total of 180 fish was divided into 4 groups of 3 replicates each. Each replicate contained 15 fish. The formulated diets were supplemented with prebiotic (Sargassum muticum), probiotic (Parkia biglobosa) and symbiotics (a combination of Parkia biglobosa and Sargassum muticum). Efficiency of the inclusion of prebiotics, probiotics and symbiotics in formulated diets was evaluated in African catfish, Clarias gariepinus fingerlings (mean weight 2.53&plusmn;0.05g). Formulated diet was fed 5% body weight to a group of 15 fish (in 3 replica) for 12 weeks, compared to fish fed control pellet containing similar ingredients but was not supplemented. Results showed on the skin of fish fed probiotics diet recorded improved GST and SOD activity and less CAT activity whereas in the liver fish fed prebiotic and symbiotic diet showed improved GST and CAT activity relative to the control. There were significant (p&lt;0.05) differences between fish fed the control diet and all treatments (prebiotic, probiotic, symbiotics). It may be concluded based on the results recorded in this study that prebiotics, probiotics and symbiotics supplementation in diets has positive effect on antioxidant enzyme activity in African catfish, Clarias gariepinus to improve resistance against bacterial infections. Key words: African catfish, antioxidant enzyme, feed utilization, growth, diets. &nbsp

Growth and health responses to a long-term pH stress in Pacific white shrimp Litopenaeus vannamei

Environmental pH change is a challenge for growth and health of aquatic animals. In this study, the juveniles of Pacific white shrimp Litopenaeus vannamei were exposed to a higher pH 9.5 or a lower pH 6.5 versus a normal pH (pH 8.0) as the control for four weeks. Growth performance, antioxidant capacity, immune functions, and intestinal histological damage and microbiota were evaluated. The weight gain rate was significantly decreased in shrimp at pH 9.5 compared with the control shrimp at pH 8.0. The antioxidant capacities of shrimp as activities of SOD, GSH-Px, GST and MDA contents shown at pH 9.5 or pH 6.5 were significantly reduced relative to the control shrimp. The expressions of immune-related genes, including anti-lipopolysaccharide factor, lysozyme, protein toll, immune deficiency, and hemocyte protein-glutamine gamma-glutamyltransferase, were down-regulated and the intestine tissues were distorted. Histology analysis showed that shrimp gut epithelial cells at pH 6.5 separated from the basement membrane, while epithelial cell necrosis were found in shrimp at pH 9.5. The diversity of intestine microbiota was disturbed with lower Shannon and higher Simpson indices in shrimp at pH 6.5 than the control shrimp, but no differences were found in shrimp at pH 9.5. The intestine barrier functions were weakened as the KEGG analysis shown, where functions for protein or carbohydrate digestion and absorption at pH 6.5, and for antibiotics biosynthesis, including streptomycin, penicillin, cephalosporin, novobiocin, ansamycins and vancomycin, at pH 9.5 in shrimp were significantly decreased. All finding in this study suggest that long-term lower or higher pH stress could adversely affect gut microbiota functions, thus leading to shrimp reduced growth, immunity and antioxidant capacity, and even intestine histology damage.

Rosuvastatin and retinoic acid may act as ‘pleiotropic agents’ against β-adrenergic agonist-induced acute myocardial injury through modulation of multiple signalling pathways

Cardiovascular disorders constitute the principal cause of deaths worldwide and will continue as the major disease-burden by the year 2060. A significant proportion of heart failures occur because of use and misuse of drugs and most of the investigational agents fail to achieve any clinical relevance. Here, we investigated rosuvastatin and retinoic acid for their “pharmacological pleiotropy” against high dose β-adrenergic agonist (isoproterenol)-induced acute myocardial insult. Rats were pretreated with rosuvastatin and/or retinoic acid for seven days and the myocardial injury was induced by administering isoproterenol on the seventh and eighth day. After induction, rats were anaesthetized for electrocardiography, then sacrificed and different samples were collected/stored for various downstream assays. Myocardial injury with isoproterenol resulted in increased cardiac mass, decreased R-wave amplitude, increased QRS and QT durations; elevated levels of cardiac markers like cTnI, CK-MB, ALT and AST; increased lipid peroxidation, protein carbonylation and tissue nitric oxide levels; decreased endogenous antioxidants like SOD, CAT, GR, GST, GPx and total antioxidant activity; increased inflammatory markers like TNF-α and IL-6; decreased the mRNA expression of Nrf2 and Bcl-2; increased the mRNA expression of Bax, eNOS and iNOS genes. Pretreatment with rosuvastatin and/or retinoic acid mitigated many of the above biochemical and pathological alterations. Our results demonstrate that rosuvastatin and retinoic acid exert cardioprotective effects and may act as potential agents in the prevention of β-adrenergic agonist-induced acute myocardial injury in rats. Cardioprotective potential of rosuvastatin and retinoic acid could be attributed to their influence on the redox pathways, immunomodulation, membrane stability, Nrf2 preservation, iNOS and Bax expression levels. Thus, they may act directly or indirectly at various steps, the breakpoints, in the pathophysiological cascade responsible for cardiac injury. Our study gives insights about the pharmacological pleiotropism of rosuvastatin and retinoic acid.

Cytoprotective Effects of Zingiber officinale Against the Oxidative Stress Induced by Lead Acetate Toxicity in Rats

The evaluation of the effect of ginger on the modulation of toxic effects induced by lead is the objective of our study. Forty male rats were randomly divided into four groups and treated daily for 3 consecutive months. Group I (0-0) was kept as control; group II (0-G) received an experimental diet with 2% of ginger; group III (Pb-0) received 2% lead acetate dissolved in drinking water with a normal diet; and group IV (Pb-G) received 2% lead acetate in drinking water and an experimental diet containing 2% ginger. Lead acetate exposure caused a significant increase of organosomatic indexes, hepatic, lipid, and urine profiles. In addition, lead acetate has a pro-oxidative effect expressed by a significant decrease in tissue GSH levels and the enzymatic activity of GPx and CAT. This pro-oxidative action was also marked by an increase in MDA level and GST activity in lead-treated group. Feeding ginger-supplemented diet to lead acetate-treated rats restored all the parameters studied as compared to control. These results suggest that ginger treatment exerts a protective effect on metabolic disorders by decreasing the oxidative stress.

Enzyme assays and toxicity of pig abattoir waste in Eisenia andrei

Due to high global demand, large amounts of abbattoir waste are generated from pork production. Mismanagement of abattoir waste on agricultural lands can result in soil and water contamination with pathogens and contaminants like metals and nutrients. Therefore, possible effects on soil organisms prior to application should be evaluated. Thus, the aim of this study was to determine the effects of fresh pig abattoir waste (PAWf) and waste after stabilization processes on E. andrei through tests of avoidance behavior, acute toxicity and chronic toxicity. In order to do this, the waste was evaluated fresh (i.e., non-treated), and after aerated composting (PAWa), natural composting (PAWn) and vermicomposting (PAWv). In addition, we used a natural soil with no history of agricultural use as control soil. The evaluation was based on avoidance behavior, mortality, initial and final earthworm weight, and reproduction, in addition to a set of enzyme assays formed by acetylcholinesterase, lipid peroxidation, catalase and glutathione S-transferase measured over time. The ecotoxicological results showed that PAWf and PAWa increased AChE activity at different experimental periods, while PAWn decreased activity at 14 days compared to the control. PAWf and PAWa increased TBARS levels at 7 and 14 days, respectively. CAT activity decreased at 3, 7 and 14 days in PAWv, while GST activity increased at 3 days in PAWa and at 3 and 14 days in PAWf compared to the control. In the acute toxicity test, PAWa and PAWn had a toxic effect on E. andrei, resulting in 100% mortality at 14 days of exposure. Based on our findings, pig abattoir waste should undergo vermicomposting prior to agricultural application to soils.

Standardization of tick specific biochemical tools for estimation of esterases, monooxygenases and glutathione S-transferase for characterization of acaricide resistance

Protocols to determine metabolic resistance in ticks were mainly derived from reports published using mosquitoes and agriculturally important insects without prior standardization. In the present study, biochemical assays were standardized to quantify acaricide metabolizing enzymes in tick homogenates. Three variables viz., age, number of larvae and reaction time were optimized using reference susceptible IVRI-I and deltamethrin resistant IVRI-IV (Resistance Factor = 194) tick strains. The optimum conditions for estimation of general esterases were 10–15 day old 40 larvae with 15 mins reaction time, 15–20 day old 40 larvae with 20 mins reaction time for Glutathione S- transferase, while 10–15 day old 80 larvae with 5 mins reaction time for monooxygenase. The standardized protocols were further validated in multi acaricide resistant strain (IVRI-V) and in nine field isolates having variable resistant factors to different acaricides. In all the nine heterogeneous field isolates, a significant correlation (p < .05) between resistance to synthetic pyrethroids and over-expression of esterases and monooxygenase was noticed. Similarly, esterases and GST activities were significantly correlated with resistance to organophosphates. The details of the assay protocol are explained for adoption in different laboratories.